Serotonin 5-HT2A receptor induces TGF-β1 expression in mesangial cells via ERK: proliferative and fibrotic signals

1999 ◽  
Vol 276 (6) ◽  
pp. F922-F930 ◽  
Author(s):  
Jasjit S. Grewal ◽  
Yurii V. Mukhin ◽  
Maria N. Garnovskaya ◽  
John R. Raymond ◽  
Eddie L. Greene
Keyword(s):  
Transforming Growth Factor ◽  
Mesangial Cells ◽  
Transforming Growth Factor Β1 ◽  
Oxygen Species ◽  
Extracellular Signal Regulated Kinase ◽  
Mrna Induction ◽  
Kinase C ◽  
Extracellular Signal ◽  
Signaling Components ◽  
Tgf Β1

We examined the links between fibrotic and proliferative pathways for the 5-HT2A receptor in rat mesangial cells. Serotonin (5-hydroxytryptamine, 5-HT) induced transforming growth factor-β1 (TGF-β1) mRNA in a concentration-dependent (peak at 30 nM 5-HT) and time-dependent fashion. For 10 nM 5-HT, the effect was noticeable at 1 h and maximal by 6 h. Inhibition of 1) protein kinase C (PKC), 2) mitogen- and extracellular signal-regulated kinase kinase (MEK1) with 2′-amino-3′-methoxyflavone (PD-90859), and 3) extracellular signal-regulated kinase (ERK) with apigenin attenuated this effect. The effect was blocked by antioxidants, N-acetyl-l-cysteine (NAC) and α-lipoic acid, and mimicked by direct application of H2O2. TGF-β1 mRNA induction was also blocked by diphenyleneiodonium and 4-(2-aminoethyl)-benzenesulfonyl fluoride, which inhibit NAD(P)H oxidase, a source of oxidants. 5-HT increased the amount of TGF-β1 protein, validating the mRNA studies and demonstrating that 5-HT potently activates ERK and induces TGF-β1 mRNA and protein in mesangial cells. Mapping studies strongly supported relative positions of the components of the signaling cascade as follow: 5-HT2A receptor → PKC → NAD(P)H oxidase/reactive oxygen species → MEK → ERK → TGF-β1 mRNA. These studies demonstrate that mitogenic signaling components (PKC, MEK, and oxidants) are directly linked to the regulation of TGF-β1, a key mediator of fibrosis. Thus a single stimulus can direct both proliferative and fibrotic signals in renal mesangial cells.

scholarly journals Extracellular Signal-Regulated Kinase Mediates Stimulation of TGF-β1 and Matrix by High Glucose in Mesangial Cells

2000 ◽  
Vol 11 (12) ◽  
pp. 2222-2230
Author(s):  
MOTOHIDE ISONO ◽  
M. CARMEN IGLESIAS-DE LA CRUZ ◽  
SHELDON CHEN ◽  
SOON WON HONG ◽  
FUAD N. ZIYADEH
Keyword(s):  
High Glucose ◽  
Transforming Growth Factor ◽  
Mesangial Cells ◽  
Specific Inhibitor ◽  
Mrna Levels ◽  
Erk Activation ◽  
Extracellular Signal Regulated Kinase ◽  
Extracellular Signal ◽  
Tgf Β1 ◽  
Stimulation Of

Abstract. High ambient glucose exerts its injurious effects on renal cells through nonenzymatic and enzymatic pathways, including altered signal transduction and upregulation of the transforming growth factor-β (TGF-β) system. Extracellular signal-regulated kinase (ERK), a member of the mitogen-activated protein kinase (MAPK) cascade, is activated in mesangial cells cultured in high glucose and in glomeruli of diabetic rats. However, the biologic consequences of ERK activation in the kidney have not been investigated. To clarify the role of ERK activation, mouse mesangial cells were exposed to normal (5.5 mM) or high (25 mM) glucose with or without addition of PD98059, a specific inhibitor of MAPK/ERK kinase (MEK), an upstream kinase activator of ERK. Cells that were exposed to high glucose exhibited significant increases in ERK activity, TGF-β1 expression (total protein, mRNA levels, and promoter activity), [3H]-proline uptake, and α1(I) collagen and fibronectin mRNA levels. Treatment with PD98059 (up to 25 μM) significantly inhibited these parameters. In contrast, 25 μM PD98059 had no significant effect on any of the parameters measured in cells that were exposed to normal glucose. Overexpression of MAPK phosphatase CL 100 prevented TGF-β1 promoter activation by high glucose, confirming the involvement of the MEK-ERK pathway in response to high glucose. The conclusion is that activation of ERK in mesangial cells is responsible for high-glucose-induced stimulation of TGF-β1 and contributes to the increased extracellular matrix expression.

Connective tissue growth factor antagonizes transforming growth factor-β1/Smad signalling in renal mesangial cells

2011 ◽  
Vol 441 (1) ◽  
pp. 499-510 ◽  
Author(s):  
Helen C. O'Donovan ◽  
Fionnuala Hickey ◽  
Derek P. Brazil ◽  
David H. Kavanagh ◽  
Noelynn Oliver ◽  
...  
Keyword(s):  
Growth Factor ◽  
Connective Tissue ◽  
Connective Tissue Growth Factor ◽  
Transforming Growth Factor ◽  
Mesangial Cells ◽  
Transforming Growth Factor Β1 ◽  
Tissue Growth ◽  
Transcriptional Responses ◽  
Cell Contractility ◽  
Tgf Β1

The critical involvement of TGF-β1 (transforming growth factor-β1) in DN (diabetic nephropathy) is well established. However, the role of CTGF (connective tissue growth factor) in regulating the complex interplay of TGF-β1 signalling networks is poorly understood. The purpose of the present study was to investigate co-operative signalling between CTGF and TGF-β1 and its physiological significance. CTGF was determined to bind directly to the TβRIII (TGF-β type III receptor) and antagonize TGF-β1-induced Smad phosphorylation and transcriptional responses via its N-terminal half. Furthermore, TGF-β1 binding to its receptor was inhibited by CTGF. A consequent shift towards non-canonical TGF-β1 signalling and expression of a unique profile of differentially regulated genes was observed in CTGF/TGF-β1-treated mesangial cells. Decreased levels of Smad2/3 phosphorylation were evident in STZ (streptozotocin)-induced diabetic mice, concomitant with increased levels of CTGF. Knockdown of TβRIII restored TGF-β1-mediated Smad signalling and cell contractility, suggesting that TβRIII is key for CTGF-mediated regulation of TGF-β1. Comparison of gene expression profiles from CTGF/TGF-β1-treated mesangial cells and human renal biopsy material with histological diagnosis of DN revealed significant correlation among gene clusters. In summary, mesangial cell responses to TGF-β1 are regulated by cross-talk with CTGF, emphasizing the potential utility of targeting CTGF in DN.

scholarly journals Targeted DNA oxidation by LSD1–SMAD2/3 primes TGF-β1/ EMT genes for activation or repression

2020 ◽  
Vol 48 (16) ◽  
pp. 8943-8958 ◽  
Author(s):  
Antonio Pezone ◽  
Maria Letizia Taddei ◽  
Alfonso Tramontano ◽  
Jacopo Dolcini ◽  
Francesca Ludovica Boffo ◽  
...  
Keyword(s):  
Epithelial To Mesenchymal Transition ◽  
Transforming Growth Factor ◽  
Transforming Growth Factor Β1 ◽  
Dna Oxidation ◽  
Mesenchymal Transition ◽  
Kinase C ◽  
Histone Lysine ◽  
Lysine Specific Demethylase ◽  
Tgf Β1

Abstract The epithelial-to-mesenchymal transition (EMT) is a complex transcriptional program induced by transforming growth factor β1 (TGF-β1). Histone lysine-specific demethylase 1 (LSD1) has been recognized as a key mediator of EMT in cancer cells, but the precise mechanism that underlies the activation and repression of EMT genes still remains elusive. Here, we characterized the early events induced by TGF-β1 during EMT initiation and establishment. TGF-β1 triggered, 30–90 min post-treatment, a nuclear oxidative wave throughout the genome, documented by confocal microscopy and mass spectrometry, mediated by LSD1. LSD1 was recruited with phosphorylated SMAD2/3 to the promoters of prototypic genes activated and repressed by TGF-β1. After 90 min, phospho-SMAD2/3 downregulation reduced the complex and LSD1 was then recruited with the newly synthesized SNAI1 and repressors, NCoR1 and HDAC3, to the promoters of TGF-β1-repressed genes such as the Wnt soluble inhibitor factor 1 gene (WIF1), a change that induced a late oxidative burst. However, TGF-β1 early (90 min) repression of transcription also required synchronous signaling by reactive oxygen species and the stress-activated kinase c-Jun N-terminal kinase. These data elucidate the early events elicited by TGF-β1 and the priming role of DNA oxidation that marks TGF-β1-induced and -repressed genes involved in the EMT.

Sign in / Sign up

Export Citation Format

Share Document